1. Field of the Invention
The present invention relates to an electrically conductive thin metal foil circuit trace having an adhesive backing for securement to a base. The circuit trace is firstly supported on a release sheet and is transferred therefrom and onto the base by the use of an adhesive transfer sheet.
2. Description of Prior Art
Various types of printed circuits are known. For example, U.S. Pat. No. 4,799,984 describes a method of fabricating a multi-layer circuit on a rigid ceramic substrate. However, all of these methods utilize a printing process for forming the printed circuit and firing process to form thick film conductors and insulating dielectrics on rigid insulated substrate material, such as alumina. The printing is usually effected through a screen mesh. In the above-referred to U.S. Patent, there is described an improved method of fabricating multi-layer circuits but this method still utilizes a firing step and uses solid substrates. Reference is also made to U.S. Pat. No. 4,891,242 which teaches the use of an automatic apparatus in which an ink jet head is displaced on an X-Y axis of a computer-aided machine (CAD) to form a circuit pattern instead of using the usual screen mask of the prior art. This eliminates the use of many screen masks to form a printed circuit and also saves time in designing and manufacturing as compared to the screen mask techniques. Again, with this method, it is necessary to bake a solution into the substrate.